Intermittent Dizziness with Normal Blood Pressure
For a patient with intermittent dizziness and normal blood pressure, perform the Dix-Hallpike maneuver immediately to diagnose benign paroxysmal positional vertigo (BPPV), which is the most common cause of episodic dizziness and can be treated on the spot with the Epley maneuver. 1, 2
Diagnostic Approach Based on Timing and Triggers
The key to diagnosis is identifying the timing pattern and triggers rather than relying on vague patient descriptions of the sensation 1, 2, 3:
Triggered Episodic Dizziness (Provoked by Head Movement)
- BPPV is the most likely diagnosis, accounting for 42% of vertigo cases in primary care 1
- Perform the Dix-Hallpike maneuver for posterior canal BPPV during the visit 1, 2
- If positive, immediately perform the Epley maneuver, which has a 90-98% success rate 1, 3
- If symptoms persist after 2-3 repositioning attempts, obtain MRI brain (not CT) to exclude central pathology 1
Spontaneous Episodic Dizziness (No Positional Trigger)
- Vestibular neuritis or Ménière's disease are more likely 1, 3
- Check for unilateral hearing loss, which suggests Ménière's disease 3
- Assess for nystagmus patterns: direction-changing nystagmus without head position changes, downward nystagmus, or spontaneous nystagmus indicates central nervous system pathology requiring urgent evaluation 1
Chronic Persistent Dizziness
- Consider psychiatric causes (depression, anxiety), medication effects, or vestibular compensation disorders 4, 5
Critical Physical Examination Maneuvers
Perform these specific tests to narrow the differential 1, 2:
- Orthostatic blood pressure testing: Measure supine and standing BP to detect orthostatic hypotension (≥20 mmHg systolic or ≥10 mmHg diastolic drop) 6
- Dix-Hallpike maneuver: Essential for diagnosing BPPV 1, 2
- Nystagmus assessment: Look for patterns indicating central vs. peripheral causes 1, 5
- Full neurologic examination: Assess for focal deficits suggesting central pathology 2, 3
Common Pitfalls to Avoid
Do not assume blood pressure medications are causing dizziness in stable patients 1. The European Society of Cardiology emphasizes that if blood pressure is stabilizing but dizziness persists, the dizziness is likely not caused by BP medications, and other causes should be actively searched for rather than adjusting cardiovascular therapy 1.
Avoid CT head for isolated dizziness—the diagnostic yield is less than 1% and sensitivity is only 20-40% for causative pathology 1. If imaging is needed, obtain MRI brain for atypical symptoms, central nystagmus patterns, or persistent symptoms after treatment attempts 1.
Do not prescribe meclizine for BPPV—vestibular suppressants do not address the underlying cause and may impede vestibular compensation 1. Meclizine is FDA-approved only for vertigo associated with vestibular system diseases, not for BPPV specifically 7.
Medication Review
Systematically review all medications that can cause dizziness 1, 2:
- Antihypertensives (especially alpha-blockers and beta-blockers) 6
- Diuretics 6
- Anticonvulsants 1
- Avoid benzodiazepines, as they impede vestibular compensation 1
When to Order Imaging
MRI brain (not CT) is appropriate for 1:
- Atypical or refractory symptoms after 2-3 repositioning attempts
- Central nystagmus patterns (direction-changing, downward, or spontaneous)
- Associated neurological symptoms
- Persistent isolated dizziness with high vascular risk factors
Laboratory testing is generally not required and rarely helpful in the evaluation of isolated dizziness 4, 2, 3.
Treatment Algorithm
- If Dix-Hallpike positive: Perform Epley maneuver immediately 1, 3
- If orthostatic hypotension present: Consider alpha agonists, mineralocorticoids, or lifestyle modifications 4
- If vestibular neuritis suspected: Consider steroids and vestibular rehabilitation 4, 3
- If Ménière's disease suspected: Salt restriction and diuretics 6, 3
- For persistent symptoms: Refer for vestibular rehabilitation, which is effective for both peripheral and central causes 2, 3